Combination box board machine



May 24, 1932. w. B. HADLEY COMBINATION BOX BOARD MACHINE Filed Feb. 16, 1931 i. mi.

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Patented May 24, i 1932 UNITED STATES PATENT ori-ice "WALTER B. RADLEY, OIF CHICAGO, ILLINOIS, ASSIGNOR, Y DIRECT AND MESNE AS- SIGNMENTS, TO KELLOGGr-HADLEY CORPORATION, A CORPORATION OF DELAWARE CGMBINATTON BOX BOARD MCHTNE Application tiled February 16, 1931.

This invention relates to paper-making and more particularly to a machine for makmg what is miown in the art as combination box board or paper board. ln thel manufacture of combination box board,- the web sheet or board is built up of a series of layers of bers imposed one upon the other in the form of slush pulp, all of the layers except the last layer being composed of a more or less inferior fiber upon which there is imposed a layer of slush pulp of superior quality, which layer is known as the liner, This liner is of high grade, capable of receiving printing. These several slush layers are deposited on an endless belt of felt, technically known in the art as a wet cylinder felt, and the deposition upon the felt is edected by what is lmown in the art as cylinder moulds, which serially deposit the several layers as the felt belt passes over the cylinder moulds and underneath the couch rolls. When the felt belt leaves the last cylinder mould, where it receives the liner layer, the combined layers of fibers which are to constitute the finished sheet er board is highly saturated with water, and in practice is composed of about 18% :bers and 80% water. It has heretofore been the practice to superpose upon the layers of fibers carried by the wet felt belt, a second felt belt so that the fibers are placed between `the two felt belts, and these two belts with the fibers between them are thenv passed through a series of wringer rolls, which act 'to wring out progressively more or less of the water from the fibers. After the wringer rolls are passed, the two belts'with the bers still between'them are passed between what are technically known as baby or primary presses which, under progressively increasing pressure, extract still more of the water. .At the last baby press the upper belt or felt is lifted or removed 'from the surface of the sheet and the'latter is then carried on the lower or wet felt belt to a cylinder ress or presses, and, as it emerges from the 'nal cylinder press,'the sheet is of sucient lconsistency and suciently dry to be passed to a series of dry rolls, while the wet cylinder felt belt is returned over a proper system of Serial No. 516,163.

rolls to'the cylinder moulds to complete the operation.

ln passing the sheet of fibers between the series of rolls constituting wringers and primary presses there is a tendency to produce l relative movement between the two felt belts, the one below and the one above the board, and in the delicate condition of the fibers at 'this stage there is a tendency to move the fibers with relation to each other in such a way as to disrupt or break their matted or cohesive co-ndition. This results in a weakened board. Furthermore, the wringer rolls and the primary press rolls act under great pressure, this being necessary to eii'ect their function of pressing the water out of the mass of iibers. This compression necessarily results in the use of a larger amount of fibers to produce a board of given thickness than would be the case if the board were made without subjecting it to this pressure.

l fOne of the objects of the present invention is to avoid the weakening of the finished sheet by reason of the relative motion between the two felt belts indicated above, thereby producing a stronger sheet. A further object is to produce a sheet of the desired thickness with a reduced amount of pulp or paper stock, thereby producing a sheet of paper board as strong as that heretofore produced by the use of the wring'er rolls and primary presses indicated above,

but with a reduced amount of fibers or stock entering into the board.

With these and other objects in view, the present invention, generally stated, consists in depositing the slush pulp fibers upon the wet felt belt serially in a plurality of layers as heretofore practiced, and then extracting the water from said fibers thus imposed upon the wet felt belt without the application of the excessive pressure heretofore employed, or, if desired, without. the application of pressure at all. This is acomplished without placing the layer of fibers between a plurality of belts and without the action of rolls as heretofore, which not only compressed the fibers beyond the desired degree, but produced the weakening effect above indicated. As more specifically stated, and in its preferredl form, the. invention consists in passing the wet felt belt from the hner cyhnder over a series of suction boxes whereby, through the action of a vacuum produced in said boxes in the usual or any desired manner, the water is extracted from the layer of fibers. Just prior to passing the wet felt belt with the fibers thereon to said suction boxes, the same is passed over a suction couch, and as the belt with the fibers leaves the suction boxes, it is passed over a final suction couch. In order to prevent injury to the wet felt belt as the same passes over the -suction boxes, a suitable foraminous belt,

preferably in the form of the well' known Fourdrinier wire is passed around the two suction couches and over the surface of the suction boxes with the wet felt belt, carrying the superimposed fibers, resting thereon, the foraminous belt and wet felt belt being driven at the same speed. From the final suction couch the wet felt belt is passed over a suction press roll, either with or with out a top press roll, and from the suction press roll the wet felt belt is returned, to repeat' the operation while the sheet passes to the driers. By this means the completed box board is secured without subjecting the same to the compression incident to the old practice and without the disrupting effect of the rolls heretoforeJ used. Furthermore, this is effected without injury to the expensive wet felt belt.

The inventive idea is capable of receiving a variety of mechanical expressions, one of which for the purpose of illustrating the invention is diagrammatically shown in the accompanying drawings, but it is to be expressly understood that such drawings are for the purpose of illustration only, and are not designed to define the limits of the invention, reference being made to the appended claims for this purpose.

In said drawings:

Fig. 1 is a diagrammatic side elevation of the invention; and

Fig. 2 is a like diagrammatic plan view thereof. y

Referring to the drawings in which like reference numerals indicate like parts through the several views, 1, 2, 3, 4, 5 and 6 indicate the usual or any desired form of cylinder moulds, 6 being the cylinder mould for applying the liner to the sheet. It will be understood that any desired number of cylinder moulds may be employed. 7 is the vat from which the fibers in the form of slush pulp are delivered to the cylinder mould 1, the fibers being supplied to the slush pulp vat 7 in the usual way throu h the under-current pipe 8. Similar slush pu p vats are associated with each of the cylinder moulds 2, 3, 4', 5 and 6, such vats not being here shown as they are well known in the art and constitute no part of the present invention. l', 2', 3', 4', 5 and 6 indicate the usual couch moulds cooperating with the respective cylinder rolls, as in ordinary practice. The wet felt belt 9 passes over the series of cylinder moulds as in prior practice and the fibers are delivered by the cylinder moulds to the underside of the wet felt belt 9. Upon leaving the liner mould 6, the wet felt belt is passed around the usual or any suitable drum roll 10, and from thence to the first suction couch roll l1, with which, if desired, a rubber-faced roll may cooperate. A foraminous belt, preferably of metal, and preferably-in the form of the well known Fourdrinier wire, 12 passes around the suc,

tion couch roll 11 and over a series of suction boxes 13 and around a second suction couch roll 14, and thence back to the first suction couch roll 11, the usual or any suitable stretcher and supporter rolls intervening.

7When the wet felt from the drum roll 10I is passed over the first couch roll 1l, it is imposed upon the foraminous belt l2, the fibers now being on top of the wet felt belt. By the use of suitable speed control apparatus of the usual or any desired form, the wet felt belt 9 and the foraminous belt l2 are driven at a uniform speed, so that there is no relative movement between the two belts. As the belt 9 passes over the suction boxes 13, the water is extracted thereby from the fibers. From the second suction couch roll 14 the foraminous belt 12 returns to repeat the operation, and the wet felt belt with the fiber sheet imposed thereon and with the water largely removed therefrom passes to a suction roll 15, and thence returns around the usual or suitable carrying and stretching rolls to repeat the operation, while the finished strip of paper board 16 passes onward for any further treatment as is usual in the paper-making art.

Preferably, though not necessarily, the solid roll 17 cooperates with the suction roll 15. Its action, however, on the strip of paper board occurring after most of the water originally in said board has been extracted therefrom, and hence its use does not result in the severe compression of said board incident to the use of the wringer and primary press rolls previously employed.

It will be readily seen that by the present invention the mass of fibers, after they leave the liner cylinder mould, are not subjected to the wringing and compressive action heretofore employed, and in fact, if so desired, can leave the suction roll without any pressure having been applied thereto, since the rubber-faced roll cooperating with the suction couch roll 11, and the solid roll 17 cooperating with the suction roll 15, may be omitted if found desirable. Moreover, it will further be seen that there is no action of any part on the fibers tending to disrupt the cohesion of the ibers, and hence to weaken the finished board.

One of the great advantages incident to the use of the foraminous belt 12 lies in the fact that Without such belt the felt would be sucked downward into depending ridges against the edge of the slots 18 in the suction boxes 13, which would produce a dest-ructive wear upon the wet felt belt, and as this is one of the most expensive elements of the equipment, it is a matter of highest importance to avoid this wear. By placing the foraminous belt 12 between the wet felt belt and the flat tops of the suction boxes, this 15 We'ar of the felt is avoided. It will, of course, be understood that the Y various cylinder moulds, suction couch rolls, drum roll, etc. are driven in the usual or any suitable manner common in paper-making plants, and the respective speeds of said parts controlled in the usual or any suitable manner. Since such driving and control mechanisms form no part of the present invention, they have not been illustrated herein. What is claimed is:

l. In a combination box board machine, theA combination of a wet felt belt, means depositing a plurality of superimposed layers of slush pulp on said belt, a plurality of suction boxes, a metallic oraminous belt passing over said boxes, and means passing said wet felt belt over said boxes with said felt belt resting on said foraminous belt..

2. In a Combination box board machine, the combination of a wet felt belt, means depositing a plurality of superimposed layers of slush pulp on said belt, a plurality of suction couch rolls, a plurality of suction boxes located between said rolls, a metallic foraminous belt passing over said rolls and boxes, and Jrneans` passing said wet felt belt with the layers of slush pulp thereon over said couch rolls and boxes and resting upon said foraminous belt.

45 In testimony whereof- I have signed this ,'.pecication WALTER B. HADLEY. 

